A and B show a Clegg Hammer, which is used to assess surface compaction. C shows a sheer vane tester, which is used to assess surface horizontal properties. The shear Vane is rotated slowly until the sample fails to estimate the shear strength.

You can take the scientist to the racetrack, but is it possible to take the racetrack to the scientist?

A research article, published in the open-access journal, PLoS ONE, suggests you can.

The Track Testing Device (TTD) was attached to a portable frame that was placed on top of the surface at the racetracks and to a fixed frame in the laboratory. The TTD dropped a 27.8 kg, 12.7 cm diameter mass from 20.3, 30.5, and 40.6 cm to simulate the effective mass, surface area, and impact velocity of the hoof during fast trot and slow gallop. Forces and linear displacement were collected at 2 kHz using custom software .Racetrack surfaces present a risk in terms of racehorse injuries and fatalities.

Current research indicates that race surface mechanical properties may be influenced by material composition, moisture content, temperature, and maintenance.

Mechanical testing of race surfaces in a controlled laboratory setting would allow for objective evaluation of dynamic properties of surface and factors that affect surface behavior.

American researchers set out to develop a method for reconstruction of race surfaces in the laboratory and then validate the method by comparing its performance with the actual racetrack surface.

Track-testing device (TTD) impact tests were conducted to simulate equine hoof impact on dirt and synthetic race surfaces; tests were performed both at the racetrack and using laboratory reconstructions of harvested surface materials.

Clegg Hammer measurements were used to guide surface reconstruction in the laboratory.

Dynamic surface properties were compared between the real track and recreated surface in the laboratory. The researchers found the differences were small.

“Clegg Hammer measurements were more strongly correlated with TTD measurements on the synthetic surface than the dirt surface. On the dirt surface, Clegg Hammer decelerations were negatively correlated with TTD forces.

“Laboratory reconstruction of racetrack surfaces guided by Clegg Hammer measurements yielded TTD impact measurements similar to in situ values. The negative correlation between TTD and Clegg Hammer measurements confirms the importance of instrument mass when drawing conclusions from testing results.

“Lighter impact devices may be less appropriate for assessing dynamic surface properties compared to testing equipment designed to simulate hoof impact (TTD).”

The researchers said their research showed that dynamic impact properties of race surfaces could be evaluated in a laboratory setting, allowing for further study of factors affecting surface behavior under controlled conditions.